1DPOTRS(1)                LAPACK routine (version 3.1)                DPOTRS(1)
2
3
4

NAME

6       DPOTRS - a system of linear equations A*X = B with a symmetric positive
7       definite matrix A using the Cholesky factorization A = U**T*U  or  A  =
8       L*L**T computed by DPOTRF
9

SYNOPSIS

11       SUBROUTINE DPOTRS( UPLO, N, NRHS, A, LDA, B, LDB, INFO )
12
13           CHARACTER      UPLO
14
15           INTEGER        INFO, LDA, LDB, N, NRHS
16
17           DOUBLE         PRECISION A( LDA, * ), B( LDB, * )
18

PURPOSE

20       DPOTRS  solves  a  system  of linear equations A*X = B with a symmetric
21       positive definite matrix A using the Cholesky factorization A =  U**T*U
22       or A = L*L**T computed by DPOTRF.
23
24

ARGUMENTS

26       UPLO    (input) CHARACTER*1
27               = 'U':  Upper triangle of A is stored;
28               = 'L':  Lower triangle of A is stored.
29
30       N       (input) INTEGER
31               The order of the matrix A.  N >= 0.
32
33       NRHS    (input) INTEGER
34               The  number of right hand sides, i.e., the number of columns of
35               the matrix B.  NRHS >= 0.
36
37       A       (input) DOUBLE PRECISION array, dimension (LDA,N)
38               The triangular factor U or L from the Cholesky factorization  A
39               = U**T*U or A = L*L**T, as computed by DPOTRF.
40
41       LDA     (input) INTEGER
42               The leading dimension of the array A.  LDA >= max(1,N).
43
44       B       (input/output) DOUBLE PRECISION array, dimension (LDB,NRHS)
45               On  entry, the right hand side matrix B.  On exit, the solution
46               matrix X.
47
48       LDB     (input) INTEGER
49               The leading dimension of the array B.  LDB >= max(1,N).
50
51       INFO    (output) INTEGER
52               = 0:  successful exit
53               < 0:  if INFO = -i, the i-th argument had an illegal value
54
55
56
57 LAPACK routine (version 3.1)    November 2006                       DPOTRS(1)
Impressum